YouTube faces a "potential News of the World" moment, a market analyst has warned, after another wave of advertisers have boycotted the video platform over their ads appearing next to inappropriate content.

Liberum warned "many more of these stories" are expected to appear because of "an inability of the algorithms to pick up and remove" unsafe material.

"Put bluntly, we doubt very much YouTube’s ability to produce automated algorithms that will do the job and the manual staffing requirements needed to police material are likely to be huge (and also something that would be difficult to outsource to cheaper countries)," Liberum’s note said.

"What YouTube faces here is a potential News of the World moment, i.e. advertisers get so fed up with the repeated stories that they eventually pull their ads altogether. This is especially true as the newspapers in particular (a) are likely to have plenty of material and examples to work with and (b) have a vested interest in exposing YouTube’s problems."

In 2011 News of the World, also part of News UK's predecessor News Corporation, closed after 168 years after revelations about the Sunday tabloid's phone-hacking activities prompted an exodus of clients pulling their ads.

Google told Campaign it would not comment further on today's analyst note and referred to a statement it released on 24 November following Brandcast: "Content that endangers children is abhorrent and unacceptable to us. We have recently toughened our approach and just in the past week we've disabled comments on thousands of videos that we've identified as of potential interest to predators and shut down hundreds of accounts identified as making predatory comments.

"There shouldn’t be any ads running on this content and we are working urgently to fix this. Over the past year, we have been working to ensure that YouTube is a safe place for everyone and while we have made significant changes in product, policy, enforcement and controls, we will continue to improve."